1. Field
One embodiment of the invention relates to an image processing apparatus and an image processing method.
2. Description of the Related Art
Various technologies have been proposed for image signal compression. For example, Japanese Patent Application Publication (KOKAI) No. 2001-359117 discloses a conventional technology, in which, upon receipt of an image signal including a color difference signal and a luminance signal through an image receiver, the information amount of the color difference signal is reduced when the image signal represents a moving image. Thus, the color difference signal is compressed together with the luminance signal.
Meanwhile, with the widespread of high-resolution televisions and displays, the resolution of image signals becomes higher. As the resolution of an image signal increases, the data volume involved in image processing on the image signal increases. Therefore, there is a need for a technology capable of more efficient image processing. Accordingly, there has been proposed the technology of image processing referred to as super resolution processing. In the super resolution processing, an original pixel value is estimated from a low-resolution image signal, and the pixels are increased to obtain a high-resolution image signal. Thus, the super resolution processing increases the resolution of an image signal while maintaining the sharpness thereof. To handle image signals with high data volume, the super resolution processing is required to be performed efficiently.
The conventional technology described above is capable of reducing the data volume of an image signal when compressing the image signal. However, it is not considered that the super resolution processing is performed on the image signal, and thus this technology cannot be used directly. Besides, with the conventional technology, a luminance signal is compressed with a color difference signal of which the information amount has been reduced. This degrades image quality, and the degradation may become significant due to the super resolution processing.